How to Build Your Own Custom AirTags

BY Sanuj Bhatia

Published 5 Mar 2021

custom airtags diy

At this point, we’re just tired of waiting for Apple to release its AirTags. Well, a team of researchers from TU Darmstadt University has taken things into their own hands and released an open-source project that can be used to build custom AirTags.

Apple has taken forever to release the AirTags. Its first existence was found way back in 2019 when an asset of AirTags leaked in iOS 13.2 code. Since then, a lot of information about them has leaked, to the point that third-party accessories have already leaked online. Now, a team at TU Darmstadt University has reverse-engineered the protocol used by Apple devices to participate in Find My Network, called OpenHayStack. The team has also released free resources for those who would like to create their own set of AirTags.

How it All Works

The application built by developers flashes custom software on a Bluetooth board, such as BBC Micro: Bit, which then emulates an Apple Find My device. Once the board is loaded with the code, it acts as a normal item tracker, broadcasting a ‘Bluetooth advertisement’ to nearby Apple devices. When an Apple device receives this Bluetooth advertisement, it sends the location (via GPS) to Apple’s Find My Network.

Pre-Requisites

Before we begin explaining how you can build your own AirTags, you need to keep a few things in mind. You’ll need a Mac running macOS Big Sur and a Bluetooth board like BBC Micro: bit, that will emulate AirTags. Micro: bit is a small development board that consists of an SoC which integrates Bluetooth Low Energy. The project supports Micro: a bit out of the box.

Note: All the software, and the resources, are taken from seemoo-lab’s Github page. They have explained in great detail how each component works. Please note that iPhoneHacks has no affiliation with OpenHayStack. Please use the guide at your own risk.

How to Build Custom AirTags

Installing OpenHayStack

The project requires you to install OpenHayStack. This software enables you to flash the required software to the Bluetooth board. It can be downloaded from here.

    • Download and double-click on the file.
    • Install OpenHayStack Mail plugin.
    • Open Terminal and run: sudo spctl –master-disable
    • Go to Apple Mail -> Preferences -> General -> Manage Plug-Ins and check OpenHaystackMail.mailbundle
    • Click on Allow
    • Open Terminal and run: sudo spctl –master-enable

Deploying Image to BCC Micro:Bit

    • Connect your Bluetooth board to your Mac.
    • Open the OpenHayStack application
    • Click on ‘Generate Key and Deploy
    • Enter a name for your Custom AirTag
    • Select an icon for your custom AirTag

That’s it. Now you’ll start seeing the location of your custom AirTag on your Mac’s Find My app after 30 minutes. You can click on every item to check when the last update was received. By clicking the reload button, you can update the location reports.